U.S. patent application number 16/742794 was filed with the patent office on 2020-07-16 for unitary housing.
The applicant listed for this patent is Mahindra and Mahindra Limited. Invention is credited to Maxson GOMES, Anil HIRGUDE, Mahendra JAWARE, Savant KEDARNATH, Rajendra N. YEDEKAR.
Application Number | 20200221626 16/742794 |
Document ID | / |
Family ID | 71517944 |
Filed Date | 2020-07-16 |
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United States Patent
Application |
20200221626 |
Kind Code |
A1 |
GOMES; Maxson ; et
al. |
July 16, 2020 |
Unitary Housing
Abstract
The present disclosure envisages a unitary housing for housing
hydraulic components, wherein the hydraulic components are
configured for operating a hitch mechanism of a tractor. The
unitary housing comprises cavities for locating valve mechanisms
therein and a cylinder for accommodating a reciprocating piston.
The unitary housing together with a plurality of valve mechanisms
disposed in corresponding cavities, forms a predetermined hydraulic
circuit. The hydraulic circuit has minimum number of leakage
joints, minimizes number of components and therefore assembly and
machining operations.
Inventors: |
GOMES; Maxson; (Mumbai,
IN) ; HIRGUDE; Anil; (Mumbai, IN) ; JAWARE;
Mahendra; (Mumbai, IN) ; KEDARNATH; Savant;
(Mumbai, IN) ; YEDEKAR; Rajendra N.; (Mumbai,
IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Mahindra and Mahindra Limited |
Mumbai |
|
IN |
|
|
Family ID: |
71517944 |
Appl. No.: |
16/742794 |
Filed: |
January 14, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A01B 59/002 20130101;
F15B 1/26 20130101; F15B 2215/30 20130101; B33Y 80/00 20141201;
A01B 63/10 20130101 |
International
Class: |
A01B 59/00 20060101
A01B059/00; F15B 1/26 20060101 F15B001/26; A01B 63/10 20060101
A01B063/10 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 14, 2019 |
IN |
201921001600 |
Claims
1. A unitary housing for housing hydraulic components, said
components configured for operating a hitch mechanism of a vehicle,
said unitary housing comprising: cavities for placing a plurality
of valve mechanisms therein; and a cylinder for accommodating a
reciprocating piston.
2. The unitary housing as claimed in claim 1, which is provided
with: at least one inlet port in fluid communication with a pump; a
plurality of channels; and at least one outlet port in fluid
communication with a sump.
3. The unitary housing as claimed in claim 2, wherein said unitary
housing, together with a plurality of valve mechanisms disposed in
said cavities in a one-to-one correspondence, forms a hydraulic
circuit configured to operate a hitch mechanism of a vehicle.
4. The unitary housing as claimed in claim 1, wherein said valve
mechanisms include at least one of: a main spool valve mechanism, a
relief valve mechanism, an unloading valve mechanism, a compensator
valve mechanism, a check valve mechanism, and an isolator valve
mechanism.
5. The unitary housing as claimed in claim 4, wherein said check
valve mechanism comprises: a poppet; a ball; a poppet spring; a
valve sleeve; a retainer; a retainer spring; and a spacer.
6. The unitary housing as claimed in claim 5, wherein said spacer
is hollow cylindrical in shape and is provided with at least one
lateral through hole to allow passage of hydraulic fluid
therethrough.
7. The unitary housing as claimed in claim 1, wherein said housing
is a casting component comprising a cylindrical cavity
corresponding to the cylinder.
8. The unitary housing as claimed in claim 7, wherein said channels
and said valve cavities are generated by performing a milling
operation on said casting component.
9. The unitary housing as claimed in claim 1, wherein said housing
is of cast iron, aluminium or ductile iron.
10. The unitary housing as claimed in claim 1, wherein said housing
is manufactured using an additive manufacturing process selected
from a group consisting of stereolithography, selective laser
sintering, laser fusing, 3D printing, electron beam melting.
11. A hitch mechanism for a tractor, said hitch mechanism provided
with a unitary housing for housing hydraulic components, said
unitary housing comprising: cavities for placing a plurality of
valve mechanisms therein; and a cylinder for accommodating a
reciprocating piston.
12. The hitch mechanism as claimed in claim 11, wherein said
unitary housing further comprises: at least one inlet port in fluid
communication with a pump; a plurality of channels; and at least
one outlet port in fluid communication with a sump.
13. A tractor having a hitch mechanism, the hydraulic components of
which are housed in a unitary housing, said unitary housing
comprising: cavities for placing a plurality of valve mechanisms
therein; a cylinder for accommodating a reciprocating piston; at
least one inlet port in fluid communication with a pump; a
plurality of channels; and at least one outlet port in fluid
communication with a sump.
Description
FIELD
[0001] The present disclosure relates to hydraulic control
components in a vehicle.
BACKGROUND
[0002] The background information herein below relates to the
present disclosure but is not necessarily prior art.
[0003] A hydraulically-controlled three-point hitch mechanism of a
vehicle such as a tractor requires a control valve housing, a
powertrain and internal position control and draft control
linkages. The control valve housing, through which the functions of
system relief, compensation, unloading and the like are executed,
is the most critical component of the hydraulic hitch control
system.
[0004] Input to the hydraulic control valve housing is hydraulic
flow and output thereof is hydraulic pressure to the powertrain of
the three-point hitch mechanism, the output pressure being
regulated by actuation of various valves contained in the hydraulic
control valve housing. A piston-cylinder mechanism is the first
component of the powertrain of the three-point hitch mechanism
which receives hydraulic power from the hydraulic control valve
housing.
[0005] Currently available hydraulic control valve housing is an
assembly of a cylinder head and a valve body coupled with a
cylinder, wherein the cylinder combines with a piston coupled with
the rest of the powertrain of the three-point hitch mechanism. The
primary issue with such an assembly of the hydraulic control valve
housing is the creation of possible leakage joints between the
mating faces, which worsen during high-pressure applications. Also,
any minor error such as looseness in fixing the components of the
hydraulic control valve housing together would lead to misalignment
of critical components. In case of high pressure operation, the
resultant high load on the piston may cause deflection of the
cylinder and therefore misalignment at the joints, which is
undesirable, since any deflection may lead to additional
misalignment and therefore leakage and wear and tear of moving
components such as the piston and the cylinder.
[0006] Hence, there is need of a hydraulic control valve housing
which ameliorates the aforementioned issues.
OBJECTS
[0007] Some of the objects of the present disclosure, which at
least one embodiment satisfies, are as follows:
[0008] A primary object of the present disclosure is to provide a
hydraulic control valve housing for a hydraulic mechanism of a
vehicle such as a tractor.
[0009] Another object of the present disclosure is to provide a
hydraulic control valve housing for a hydraulic hitch mechanism of
a vehicle.
[0010] Yet object of the present disclosure is to provide a
hydraulic control valve housing for a hydraulic hitch mechanism of
a vehicle, which eliminates leakage joints.
[0011] Still object of the present disclosure is to provide a
hydraulic control valve housing for a hydraulic hitch mechanism of
a vehicle, which prevents misalignment of moving components.
[0012] Other objects and advantages of the present disclosure will
be more apparent from the following description, which is not
intended to limit the scope of the present disclosure.
SUMMARY
[0013] The present disclosure envisages a unitary housing for
housing components for operating a hitch mechanism of a vehicle
such as a tractor. The unitary housing comprises cavities for
placing a plurality of valve mechanisms therein and a cylinder for
accommodating a reciprocating piston.
[0014] The unitary housing is provided with at least one inlet port
in fluid communication with a pump, a plurality of channels and at
least one outlet port in fluid communication with a sump.
[0015] In an embodiment, the unitary housing, together with a
plurality of valve mechanisms disposed in the cavities in a
one-to-one correspondence, forms a hydraulic circuit configured to
operate a hitch mechanism of a vehicle.
[0016] In another embodiment, the plurality of valve mechanisms
includes at least one of a main spool valve mechanism, a relief
valve mechanism, an unloading valve mechanism, a compensator valve
mechanism, a check valve mechanism and an isolator valve mechanism.
In yet another embodiment, the check valve mechanism comprises a
poppet, a ball, a poppet spring, a valve sleeve, a retainer, a
retainer spring and a spacer. The spacer is hollow cylindrical in
shape and is provided with at least one lateral through hole to
allow passage of hydraulic fluid therethrough.
[0017] In still another embodiment, the housing is a casting,
wherein the casting component comprises a cylindrical cavity
corresponding to the cylinder. In yet another embodiment, the
channels and the valve cavities are generated by performing a
milling operation on the casting component. In still another
embodiment, the housing is of cast iron.
[0018] In still another embodiment, the housing is manufactured
using an additive manufacturing process selected from a group
consisting of stereolithography, selective laser sintering, laser
fusing, 3D printing, electron beam melting.
[0019] The present disclosure further envisages a hitch mechanism
for a tractor. The hitch mechanism is provided with a unitary
housing for housing hydraulic components. The unitary housing
comprises cavities for placing a plurality of valve mechanisms
therein, and a cylinder for accommodating a reciprocating
piston.
[0020] In an embodiment, the unitary housing further comprises at
least one inlet port in fluid communication with a pump, a
plurality of channels, and at least one outlet port in fluid
communication with a sump.
[0021] The present disclosure also envisages a tractor having a
hitch mechanism, the hydraulic components of which are housed in a
unitary housing. The unitary housing comprises cavities for placing
a plurality of valve mechanisms therein, a cylinder for
accommodating a reciprocating piston, at least one inlet port in
fluid communication with a pump, a plurality of channels, and at
least one outlet port in fluid communication with a sump.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWING
[0022] FIG. 1 illustrates a schematic diagram of a hydraulic
control valve circuit of a first prior art;
[0023] FIG. 2a illustrates an exploded view of a hydraulic control
valve housing assembly of FIG. 1;
[0024] FIG. 2b illustrates a hydraulic control valve housing
assembly of FIG. 1;
[0025] FIG. 3 illustrates a hydraulic control valve housing
assembly of a second prior art;
[0026] FIG. 4a illustrates a schematic diagram of fluid flow in a
hydraulic control valve housing assembly of FIG. 1;
[0027] FIG. 4b illustrates a schematic diagram of the fluid flow in
the hydraulic control valve housing assembly of FIG. 3;
[0028] FIG. 5 illustrates a schematic diagram of the hydraulic
control valve circuit of the present disclosure;
[0029] FIG. 6a illustrates a rear-isometric view of a unitary
housing of an embodiment of the present disclosure in the
pre-machined stage;
[0030] FIG. 6b illustrates a front-isometric view of the unitary
housing of FIG. 6a;
[0031] FIG. 7a illustrates the unitary housing of FIG. 6a in the
post-machined stage;
[0032] FIG. 7b illustrates a left-isometric view of the unitary
housing of FIG. 7a;
[0033] FIG. 8a illustrates a sectional view of the unitary housing
of FIG. 7a;
[0034] FIG. 8b illustrates another sectional view of the unitary
housing of FIG. 7a;
[0035] FIG. 9a illustrates a yet another sectional view of the
unitary housing of FIG. 7a;
[0036] FIG. 9b illustrates still another sectional view of the
unitary housing of FIG. 7a;
[0037] FIG. 10 illustrates a yet another sectional view of the
unitary housing of FIG. 7a;
[0038] FIG. 11 illustrates a sectional view of a check valve of the
present disclosure;
[0039] FIG. 12a illustrates an isometric view of a solid
representation of the hydraulic circuit formed by channels of the
housing of FIG. 7a;
[0040] FIG. 12b illustrates a circuit of FIG. 12a with the valve
mechanisms and plugs installed; and
[0041] FIG. 13 illustrates a schematic diagram of fluid flow in the
hydraulic control valve housing assembly of FIG. 6b.
LIST OF REFERENCE NUMERALS
[0042] 1000' hydraulic control valve housing assembly of a first
prior art [0043] 1000'' hydraulic control valve housing assembly of
a second prior art [0044] 100' valve housing of a first prior art
[0045] 105' cylinder head of a first prior art [0046] 110' cylinder
of a first prior art [0047] 100'' valve housing of a second prior
art [0048] 115'' hydraulic housing of a second prior art [0049]
110'' cylinder of a second prior art [0050] 1000 hydraulic control
valve housing assembly of the present disclosure [0051] 100 housing
of the present disclosure [0052] 110 cylindrical cavity [0053] 122
main spool valve [0054] 124 relief valve [0055] 126 unloading valve
[0056] 128 compensator valve [0057] 130 check valve [0058] 1301
check valve poppet [0059] 1302 check valve ball [0060] 1303 check
valve poppet spring [0061] 1304 check valve sleeve [0062] 1305
check valve retainer [0063] 1306 check valve retainer spring [0064]
1307 check valve spacer [0065] 1308 check valve plug [0066] 1309
check valve face seal [0067] 132 isolator valve [0068] 134 orifice
[0069] 136 orifice filter [0070] 200 powertrain [0071] 210 piston
[0072] 220 connecting rod [0073] 300 pump [0074] 310 strainer
[0075] 320 filter [0076] 400 sump
DETAILED DESCRIPTION
[0077] Embodiments, of the present disclosure, will now be
described with reference to the accompanying drawing.
[0078] Embodiments are provided so as to thoroughly and fully
convey the scope of the present disclosure to the person skilled in
the art. Numerous details are set forth, relating to specific
components, and methods, to provide a complete understanding of
embodiments of the present disclosure. It will be apparent to the
person skilled in the art that the details provided in the
embodiments should not be construed to limit the scope of the
present disclosure. In some embodiments, well-known processes,
well-known apparatus structures, and well-known techniques are not
described in detail.
[0079] The terminology used, in the present disclosure, is only for
the purpose of explaining a particular embodiment and such
terminology shall not be considered to limit the scope of the
present disclosure. As used in the present disclosure, the forms
"a", "an" and "the" may be intended to include the plural forms as
well, unless the context clearly suggests otherwise. The terms
"comprises", "comprising", "including" and "having" are open-ended
transitional phrases and therefore specify the presence of stated
features, integers, steps, operations, elements, modules, units
and/or components, but do not forbid the presence or addition of
one or more other features, integers, steps, operations, elements,
components, and/or groups thereof. The particular order of steps
disclosed in the method and process of the present disclosure is
not to be construed as necessarily requiring their performance as
described or illustrated. It is also to be understood that
additional or alternative steps may be employed.
[0080] When an element is referred to as being "mounted on",
"engaged to", "connected to" or `coupled to" another element, it
may be directly on, engaged, connected or coupled to the other
element. As used herein, the term "and/or" includes any and all
combinations of one or more of the associated listed elements.
[0081] The terms first, second, third, etc., should not be
construed to limit the scope of the present disclosure as the
aforementioned terms may be only used to distinguish one element,
component, region, layer or section from another component, region,
layer or section. Terms such as first, second, third etc., when
used herein do not imply a specific sequence or order unless
clearly suggested by the present disclosure.
[0082] Terms such as "inner", "outer", "beneath", "below", "lower",
"above", "upper" and the like, may be used in the present
disclosure to describe relationships between different elements as
depicted from the figures.
[0083] A hydraulic control system is usually employed for
controlling actuation of a three-point hitch mechanism of a vehicle
such as a tractor, which is used for raising and lowering of an
equipment (e.g., a plough) attached to the top and the bottom links
of the three-point hitch mechanism. A hydraulic control valve
housing is a crucial component of the hydraulic control system. A
control valve housing generally is an assembly of a cylinder head,
a valve body and a cylinder which contains a piston, wherein the
piston is coupled to the powertrain of the three-point hitch
mechanism. Control of the three-point hitch mechanism is performed
through hydraulic actuation of the piston by various valve
mechanisms contained in the valve body and the cylinder head. A
main spool valve holds or diverts hydraulic flow within the
hydraulic system to lifting, lowering or tank ports as per its
defined position by the operator of the vehicle. Besides a main
spool valve mechanism, the hydraulic control system contains an
unloading valve mechanism, a relief valve mechanism, a check valve
mechanism, a compensator valve mechanism and an isolator valve
mechanism, each disclosed within a corresponding cavity acting as
the corresponding valve body. The check valve allows hydraulic flow
in one direction only and holds the hydraulic flow in reverse
direction. The compensator valve enables fixed throttling flow at
varying outlet pressures. Thus, cylinder velocity is kept constant
against variable pressures due to the compensator valve. The relief
valve controls system pressure by limiting system pressure as per a
set value. The unloading valve is a pressure-control device that is
used to dump excess fluid to tank at little or no pressure. The
isolator valve isolates flow to a given location to provide flow
logic to internal or external of the hydraulic control circuit.
[0084] One such prior art (first) is illustrated in FIGS. 1 and 2.
The schematic diagram of FIG. 1 shows a hydraulic control valve
circuit 1000', wherein the main spool valve mechanism 122, the
relief valve mechanism 124, the unloading valve mechanism 126 and
the check valve mechanism 130 are disposed in the control valve
housing 100', the compensator valve mechanism 128 and the isolator
valve mechanism 132 are disposed in the cylinder head 105', and the
cylinder 110' is attached to the control valve housing 100'. The
exploded view of the control valve housing assembly is shown in
FIG. 2a, and the assembled configuration of the control valve
housing assembly is shown in FIG. 2b. FIG. 4a illustrates flow of
fluid starting from the pump 300, through the cylinder head 105',
the control valve housing 100' and the cylinder 110' in order to
drive the powertrain 200, according to the first prior art.
[0085] Another prior art (second) is disclosed in FIG. 3. The
exploded view of the control valve housing 100'', the hydraulic
housing 115'' and the cylinder 110'' is shown in FIG. 3. FIG. 4b
illustrates flow of the fluid starting from the pump 300, through
the control valve housing 100'', the hydraulic housing 115'' and
the cylinder 110'' in order to drive the powertrain 200, according
to the second prior art.
[0086] The presence of multiple joining faces in these prior arts
increases occurrence of leakage from these joints, as also
misalignment between critical components, cylinder deflection due
to high piston load and so on. All these issues need to be
addressed by frequent servicing, which adds to the cost.
[0087] The present disclosure envisages a unitary housing 100 for
housing components for operating a hitch mechanism of a vehicle
such as a tractor, as illustrated in the schematic diagram of FIG.
5. The hydraulic circuit 1000 configured using these valves is
illustrated in the schematic diagram of FIG. 5. The unitary housing
100 comprises cavities for locating valve mechanisms therein and a
cylinder 110 for accommodating a reciprocating piston 110. The
unitary housing 100 is in fluid communication with a hydraulic pump
300. Further, the unitary housing 100 is provided with at least one
inlet port 102 (shown in FIG. 7b) in fluid communication with the
pump 300, at least one outlet port 106 in fluid communication with
a sump 400 (shown in cross-sectional views of the housing in FIGS.
8b, 9b), a plurality of valve cavities (not shown), a plurality of
channels 104 (the various channels being shown in cross-sectional
views in FIGS. 8a, 8b, 9a, 9b and 10) defining a predetermined
hydraulic network (a solid representation of the hydraulic network
of the various channels being shown in FIG. 12a) and a cylinder 110
which opens external to the unitary housing 100. The sump 400 is a
reservoir of the oil for the hydraulic network of the present
disclosure. The various control valve mechanisms are disposed
within their corresponding valve cavities formed within the unitary
housing 100. Together with the control valve mechanisms, the
hydraulic network shown in FIG. 12a forms the hydraulic circuit
shown in FIG. 12b. The piston 210 is slidingly disposed within the
cylinder 110 and is configured to be coupled with the hitch
mechanism.
[0088] In an embodiment, the plurality of valve mechanisms disposed
within the unitary housing 100 includes a main spool valve
mechanism 122, a relief valve mechanism 124, an unloading valve
mechanism 126, a compensator valve mechanism 128, a check valve
mechanism 130 and an isolator valve mechanism 132. The main spool
valve 122 is actuated by the operator of the vehicle. The pump 300
is driven by either mechanical power of the vehicle's powertrain or
by an independent battery-operated electric motor. The pump 300
draws hydraulic fluid from a sump 400 through a strainer 310 and a
filter 320 installed at its inlet. The output of the pump 300 is
connected to the inlet of the unitary housing 100. The pressurized
fluid entering the unitary housing 100 at the inlet flows into the
inlet of the compensator valve 132. One of the outlets of the
compensator valve 128 is connected to the main spool valve 122 and
the flow from the other outlet is branched to be connected to the
relief valve 124 and the unloading valve 126. The unloading valve
126 is further connected to the main spool valve 122 and an orifice
filter 136. The relief valve 124 is further connected to the main
spool valve 122. The main spool valve 122 is further connected to
the check valve 130. Fluid from the check valve 130 finally enters
the cylindrical cavity 110 through the isolator valve 132.
[0089] The unitary housing 100 is shown a pre-machined stage, as
shown in FIGS. 6a, 6b. The unitary housing 100 is first prepared as
a casting, made using conventional casting methods such as sand
casting. The cylinder 110 is obtained by using a cylindrical core
of approximately the same external diameter as the internal
diameter of the cylinder 110. Rest of the casting is solid. The
casting is made out of cast iron, although aluminium and ductile
iron can also be used. The valve cavities for inserting the
corresponding valve mechanisms and the various oil channels 104 are
obtained by performing a suitable machining operation such as
milling, using a machine such as a vertical machining centre (VMC),
and at appropriate locations in the unitary housing 100. Further,
close tolerances in diameter of the cavities and the various oil
channels 104 are achieved using surface finishing methods selected
from a group consisting of grinding, honing and the like. A
post-machined stage of the unitary housing 100 is shown in FIG. 7a.
After insertion of the valve mechanisms in the corresponding valve
cavities, the openings are closed and sealed using means such as a
plug and a face seal. The control valve assembly in a complete
state is shown in FIG. 7b. In another embodiment, the unitary
housing 100 is obtained using an additive manufacturing process
selected from a group consisting of stereolithography, selective
laser sintering, laser fusing, 3D printing, electron beam melting,
and the like. With this method, the internal cavities and various
oil channels 104 are also directly generated in the unitary housing
100. Close tolerances are further achieved using a method selected
from a group consisting of grinding, honing and the like.
[0090] In the FIGS. 8a, 8b, 9a, 9b, 10, the various cross-sectional
views of the unitary housing 100 are illustrated. FIG. 8a
illustrates the portion of the hydraulic circuit 1000 around the
compensator valve 128. FIG. 8b illustrates the portion of the
hydraulic circuit around the relief valve 124 and the unloading
valve 126. FIG. 9a illustrates the portion of the hydraulic circuit
around the main spool valve 122, the valve unloading valve 126 and
the orifice 134. FIG. 9b illustrates another portion of the
hydraulic circuit around the relief valve 124. FIG. 10 illustrates
the portion of the hydraulic circuit around the main spool valve
122, the compensator valve 128, the check valve 130 and the
cylinder 110. Different segments of the hydraulic channels 104 are
visible in each of FIGS. 8a, 8b, 9a, 9b, 10.
[0091] The check valve mechanism 130 as illustrated in FIG. 11
comprises a poppet 1301, a ball 1302, a poppet spring 1303, a valve
sleeve 1304, a retainer 1305, a retainer spring 1306 and a spacer
1307. The retainer spring 1306 is used to maintain the position of
the retainer 1305. The retainer 1305 keeps the poppet spring 1303
compressed. The spacer 1307 is hollow cylindrical in shape and is
provided with at least one lateral through hole to allow passage of
hydraulic fluid therethrough. Besides, the external opening
provided in the unitary housing 100 for inserting the mechanism 130
is plugged and sealed using a plug 1308 and a face seal 1309. By
providing the spacer 1307, an existing valve mechanism is
accommodated in the unitary housing 100 of the present disclosure,
without requiring adjustment of the compression value of the
retainer spring 1306.
[0092] The piston 210 is coupled to the arm of the sleeve of the
powertrain 200 through a connecting rod 220, as shown in FIG. 13.
The piston 210 is displaced due to hydraulic pressure of the fluid.
The magnitude of pressure and direction of flow of the fluid is as
governed by positions of the various valves in the housing 100. At
the same time, position of valves like the unloading valve 126 is
governed by back pressure received through the powertrain 200 due
to increase in draft of the implement connected to the hitch
mechanism. The power supplied to the powertrain 200 results in
raising or lowering of the implement connected to the links of the
hitch mechanism for draft control and position control.
[0093] The unitary housing 100 of the present disclosure as
illustrated in FIG. 6b eliminates the various joints present in the
aforementioned prior arts by integrating the valve housing 100',
the cylinder head 105' and the cylinder 110' of the prior art into
a unitary housing 100. The unitary housing 100 is made in the form
a single cast, and the inlet, the outlet, the attachment holes, the
valve openings and the like are provided by a suitable machining
operation. The number of leakage points is minimized by eliminating
the joints in the prior arts. Consequently, corresponding sealing
elements required in the assembly are eliminated. Any increase in
load on the piston 210 does not lead to deflection of the cylinder
110, since the cylinder 110 is integral to the unitary housing 100,
resulting in increased component life. The control valve housing
assembly of the prior art shown in FIG. 2a requires machining
operation to be performed on the cylinder head 105', the valve
housing 100' and the cylinder 110'. With lesser components involved
in the assembly, the required number of assembly operations,
testing operations and machining operations is minimized. Logistics
and storage requirements are reduced due to the reduced part
count.
[0094] The present disclosure further envisages a hitch mechanism
for a tractor. The hitch mechanism is provided with a unitary
housing (100) for housing hydraulic components. The unitary housing
(100) comprises cavities for placing a plurality of valve
mechanisms therein, and a cylinder (110) for accommodating a
reciprocating piston (210).
[0095] In an embodiment, the unitary housing (100) further
comprises at least one inlet port (102) in fluid communication with
a pump (300), a plurality of channels (104), and at least one
outlet port (106) in fluid communication with a sump (400).
[0096] The present disclosure also envisages a tractor having a
hitch mechanism, the hydraulic components of which are housed in a
unitary housing (100). The unitary housing (100) comprises cavities
for placing a plurality of valve mechanisms therein, a cylinder
(110) for accommodating a reciprocating piston (210), at least one
inlet port (102) in fluid communication with a pump (300), a
plurality of channels (104); and at least one outlet port (106) in
fluid communication with a sump (400).
[0097] The foregoing description of the embodiments has been
provided for purposes of illustration and not intended to limit the
scope of the present disclosure. Individual components of a
particular embodiment are generally not limited to that particular
embodiment, but, are interchangeable. Such variations are not to be
regarded as a departure from the present disclosure, and all such
modifications are considered to be within the scope of the present
disclosure.
Technical Advancements
[0098] The present disclosure described herein above has several
technical advantages including, but not limited to, the realization
of a housing for housing components for operating a hitch mechanism
of a vehicle such as a tractor, which: [0099] eliminates leakage
joints and corresponding sealing elements; [0100] prevents
misalignment of moving components; [0101] increases strength of the
cylinder as it is integrated with the valve body; [0102] eases
servicing; [0103] reduces part count; and [0104] reduces assembly,
machining and testing operations.
[0105] The foregoing disclosure has been described with reference
to the accompanying embodiments which do not limit the scope and
ambit of the disclosure. The description provided is purely by way
of example and illustration.
[0106] The embodiments herein and the various features and
advantageous details thereof are explained with reference to the
non-limiting embodiments in the following description. Descriptions
of well-known components and processing techniques are omitted so
as to not unnecessarily obscure the embodiments herein. The
examples used herein are intended merely to facilitate an
understanding of ways in which the embodiments herein may be
practiced and to further enable those of skill in the art to
practice the embodiments herein. Accordingly, the examples should
not be construed as limiting the scope of the embodiments
herein.
[0107] The foregoing description of the specific embodiments so
fully reveal the general nature of the embodiments herein that
others can, by applying current knowledge, readily modify and/or
adapt for various applications such specific embodiments without
departing from the generic concept, and, therefore, such
adaptations and modifications should and are intended to be
comprehended within the meaning and range of equivalents of the
disclosed embodiments. It is to be understood that the phraseology
or terminology employed herein is for the purpose of description
and not of limitation. Therefore, while the embodiments herein have
been described in terms of preferred embodiments, those skilled in
the art will recognize that the embodiments herein can be practiced
with modification within the spirit and scope of the embodiments as
described herein.
[0108] The use of the expression "at least" or "at least one"
suggests the use of one or more elements or ingredients or
quantities, as the use may be in the embodiment of the disclosure
to achieve one or more of the desired objects or results.
[0109] Any discussion of documents, acts, materials, devices,
articles or the like that has been included in this specification
is solely for the purpose of providing a context for the
disclosure. It is not to be taken as an admission that any or all
of these matters form a part of the prior art base or were common
general knowledge in the field relevant to the disclosure as it
existed anywhere before the priority date of this application.
[0110] The numerical values mentioned for the various physical
parameters, dimensions or quantities are only approximations and it
is envisaged that the values higher/lower than the numerical values
assigned to the parameters, dimensions or quantities fall within
the scope of the disclosure, unless there is a statement in the
specification specific to the contrary.
[0111] While considerable emphasis has been placed herein on the
components and component parts of the preferred embodiments, it
will be appreciated that many embodiments can be made and that many
changes can be made in the preferred embodiments without departing
from the principles of the disclosure. These and other changes in
the preferred embodiment as well as other embodiments of the
disclosure will be apparent to those skilled in the art from the
disclosure herein, whereby it is to be distinctly understood that
the foregoing descriptive matter is to be interpreted merely as
illustrative of the disclosure and not as a limitation.
* * * * *